Core/Creatures: fixed a issue where creatures that are walking on puddles are considered swimming so their gravity got enabled.

src/server/game/Entities/Unit/Unit.cpp

@@ -14152,7 +14152,8 @@ bool Unit::SetSwim(bool enable)
     if (enable)
     {
         AddUnitMovementFlag(MOVEMENTFLAG_SWIMMING);
-        SetDisableGravity(true);
+        if (IsUnderWater())
+            SetDisableGravity(true);
     }
     else
     {

src/server/game/Maps/Map.cpp

@@ -2338,15 +2338,7 @@ float Map::GetWaterOrGroundLevel(PhaseShift const& phaseShift, float x, float y,
         LiquidData liquid_status;
 
         ZLiquidStatus res = GetLiquidStatus(phaseShift, x, y, ground_z, MAP_ALL_LIQUIDS, &liquid_status);
-        switch (res)
-        {
-            case LIQUID_MAP_ABOVE_WATER:
-                return std::max<float>(liquid_status.level, ground_z);
-            case LIQUID_MAP_NO_WATER:
-                return ground_z;
-            default:
-                return liquid_status.level;
-        }
+        return res ? liquid_status.level : ground_z;
     }
 
     return VMAP_INVALID_HEIGHT_VALUE;